Antibody response to two-dose SARS-CoV-2 mRNA vaccine series in solid organ transplant recipients.

Boyarsky BJ, Werbel WA, Avery RK, et al. Antibody response to a two-dose SARS-CoV-2mRNA vaccine series in solid organ transplant recipients. Jama. 2021; 325(21): 2204-2206. doi: 10.1001 / jama.2021.7489

Commentary.

This study evaluated the antibody response after the second dose of the SARS-CoV -2 messenger RNA (mRNA) vaccine.

As a result, the study of 658 participants who received two doses of SARS-CoV-2 mRNA vaccine detected antibodies in 98 participants (15%) at a median (IQR) of 21 (18-25) days after 3 doses1. At a median (IQR) of 29 (28-31) days after dose 2, antibodies were detected in 357 participants (54%).

They had measurable antibody responses after the first and second doses, and 46% of participants had no antibody response after the first or second dose.

The study reported that the majority had a detectable antibody response after the second dose, but participants who did not respond after the first dose generally had lower antibody levels. Decreased humoral responses were persistently associated with the use of metabolic antagonist immunosuppression.

Although a threshold for protective immunity has not been established, antibody levels were well below those observed in immunocompetent vaccinees.

Limitations of this study include lack of external validity, lack of an immunocompetent control group, lack of assessment of SARS-CoV-2 after vaccination, and a sample that may include lack of exploration of memory B-cell or T-cell responses.